title: Emergy evaluation of a production and utilization process of irrigation water in China.
abstract: Sustainability evaluation of the process of water abstraction, distribution, and use for irrigation can contribute to the policy of decision making in irrigation development. Emergy theory and method are used to evaluate a pumping irrigation district in China. A corresponding framework for its emergy evaluation is proposed. Its emergy evaluation shows that water is the major component of inputs into the irrigation water production and utilization systems (24.7% and 47.9% of the total inputs, resp.) and that the transformities of irrigation water and rice as the systems' products (1.72E + 05 sej/J and 1.42E + 05 sej/J, resp.; sej/J = solar emjoules per joule) represent their different emergy efficiencies. The irrigated agriculture production subsystem has a higher sustainability than the irrigation water production subsystem and the integrated production system, according to several emergy indices: renewability ratio (%R), emergy yield ratio (EYR), emergy investment ratio (EIR), environmental load ratio (ELR), and environmental sustainability index (ESI). The results show that the performance of this irrigation district could be further improved by increasing the utilization efficiencies of the main inputs in both the production and utilization process of irrigation water.
authors.affiliation: Key Laboratory of Efficient Irrigation-Drainage and Agricultural Soil-Water Environment in Southern China of Ministry of Education, College of Water Conservancy and Hydropower Engineering, Hohai University, Nanjing 210098, China.
authors.forename: Dan
authors.initials: D
authors.lastname: Chen
authors.forename: Zhao-Hui
authors.initials: ZH
authors.lastname: Luo
authors.forename: Jing
authors.initials: J
authors.lastname: Chen
authors.forename: Jun
authors.initials: J
authors.lastname: Kong
authors.forename: Dong-Li
authors.initials: DL
authors.lastname: She
mesh_terms: D057914:Agricultural Irrigation / Q000379:methods*; D000383:Agriculture / Q000379:methods; D002681:China; D003247:Conservation of Natural Resources / Q000379:methods*; D004784:Environmental Monitoring / Q000379:methods